摘要
以200m水深导管架平台为研究对象,采用有限元方法对各疲劳子工况下平台的动力响应进行分析,确定了计算点处的传递函数,并计算出相应的应力谱;根据Miner线性疲劳累积损伤理论及结构可靠性理论对平台的疲劳寿命可靠性进行了分析;对泥面以下6倍桩径处固定的等效桩做法在深水导管架平台动力分析中的适用性进行了分析。对于深水导管架平台,采用泥面以下6倍桩径处固定的等效桩做法存在较大误差,进行动力分析时须采用桩-土耦合模型;波高较小海况下,平台结构应力谱对应于波浪主频率的峰值较小、对应于平台前两阶固有频率的峰值较大,后者是导致平台疲劳破坏的主要原因;导管架过渡段到第三水平层之间节点及泥面处节点的可靠性指标相对较小。
A jacket platform for water depth of 200 m was taken as the research object.The dynamic response analysis of the deep water jacket platform for each fatigue sub condition was performed by finite element methods,the transfer functions of the calculating points were obtained based on dynamic response analysis and then the corresponding stress spectra were calculated out.In accordance with Miner＇s linear fatigue cumulative damage rule and structure reliability theory,the fatigue life reliability of the platform was analyzed.The applicability of the equivalent pile method,fixing the deep water jacket platform at a depth of six times the pile diameters below mud line,was studied.The results indicate that the equivalent pile method can makes large error for deep water jacket platforms,so the pile-soil interaction must be considered during the dynamic response analysis;when the small wave height appears,the peak of stress spectrum is smaller at the main frequency of wave,but larger at the first two natural frequencies of platform,the latter is the main reason of fatigue failure of jacket platform;the reliability indexes of tubular joints between the transition section and the third horizontal layer,as well as tubular joints at mud line,are less than those in other locations.
出处
《中国海上油气》
CAS
北大核心
2010年第1期59-64,共6页
China Offshore Oil and Gas
基金
中石化集团公司重点攻关项目(编号:P08032)部分研究成果
关键词
深水导管架
谱分析
疲劳可靠性
传递函数
应力谱
deep water jacket platform
spectral method
fatigue reliability
transfer functions
stress spectrum
